Characterization of flavivirus infection in salivary gland cultures from male < i > Ixodes scapularis < /i > ticks

by Benjamin L. Kendall, Jeffrey M. Grabowski, Rebecca Rosenke, Mikayla Pulliam, Daniel R. Long, Dana P. Scott, Danielle K. Offerdahl, Marshall E. Bloom InfectedIxodes scapularis (black-legged tick) transmit a host of serious pathogens via their bites, includingBorrelia burgdorferi,Babesia microti, and tick-borne flaviviruses (TBFVs), such as Powassan virus (POWV). Although the role of femaleI.scapularis ticks in disease transmission is well characterized, the role of male ticks is poorly understood. Because the pathogens are delivered in tick saliva, we studied the capacity of male salivary glands (SGs) to support virus replication.Ex vivo cultures of SGs from unfed maleI.scapularis were viable for more than a week and maintained the characteristic tissue architecture of lobular ducts and acini. When SG cultures were infected with the TBFVs Langat virus (LGTV) or POWV lineage II (deer tick virus), the production of infectious virus was demonstrated. Using a green fluorescent protein-tagged LGTV and confocal microscopy, we demonstrated LGTV infection within SG acinus types II and III. The presence of LGTV in the acini and lobular ducts of the cultures was also shown via immunohistochemistry. Furthermore, the identification byin situ hybridization of both positive and negative strand LGTV RNA confirmed that the virus was indeed replicating. Finally, transmission electron microscopy of infected SGs revealed virus particles packaged in vesicles or vacuoles adjacent to acinar lum...
Source: PLoS Neglected Tropical Diseases - Category: Tropical Medicine Authors: Source Type: research